Crop yield estimation by satellite remote sensing

Abstract Two methods for estimating the yield of different crops in Hungary from satellite remote sensing data are presented. The steps of preprocessing the remote sensing data (for geometric, radiometric, atmospheric and cloud scattering correction) are described. In the first method developed for field level estimation, reference crop fields were selected by using Landsat Thematic Mapper (TM) data for classification. A new vegetation index (General Yield Unified Reference Index (GYURI)) was deduced using a fitted double-Gaussian curve to the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data during the vegetation period. The correlation between GYURI and the field level yield data for corn for three years was R 2=0.75. The county-average yield data showed higher correlation (R 2=0.93). A significant distortion from the model gave information of the possible stress of the field. The second method presented uses only NOAA AVHRR and officially reported county-level yield data. The county-level yield data and the deduced vegetation index, GYURRI, were investigated for eight different crops for eight years. The obtained correlation was high (R 2=84.6–87.2). The developed robust method proved to be stable and accurate for operational use for county-, region- and country-level yield estimation. The method is simple and inexpensive for application in developing countries, too. Acknowledgments Our dear friend and colleague, Dr György Tarcsai, died during this long research work, in which he was a very effective partner in the first half of this activity. Let this paper be a small memorial to Gy. Tarcsai. The authors sincerely thank the FÖMI Research Center for their cooperation in the starting phase of this R&D. This work was carried out within the long-range R&D funds of the Hungarian Space Office, and from some special aspects in connection with earlier and actual (T034831, T037611 and F037603) OTKA contracts of the Hungarian Academy of Sciences. Notes †Deceased. Additional informationNotes on contributorsGy. TarcsaiFootnote† †Deceased.